U.S. patent application number 14/652045 was filed with the patent office on 2015-11-12 for method for removing liquid membrane using high-speed particle beam.
This patent application is currently assigned to POSTECH ACADEMY-INDUSTRY FOUNDATION. The applicant listed for this patent is POSTECH ACADEMY-INDUSTRY FOUNDATION. Invention is credited to In Ho KIM, Jin Won LEE.
Application Number | 20150323252 14/652045 |
Document ID | / |
Family ID | 48866591 |
Filed Date | 2015-11-12 |
United States Patent
Application |
20150323252 |
Kind Code |
A1 |
KIM; In Ho ; et al. |
November 12, 2015 |
METHOD FOR REMOVING LIQUID MEMBRANE USING HIGH-SPEED PARTICLE
BEAM
Abstract
A method for removing a liquid membrane using a high-speed
particle beam includes a wet washing step of washing an object by
using a washing solution, and a dry washing step of simultaneously
removing the washing solution remaining on the object and
pollutants or foreign substances in the washing solution by
spraying sublimation particles.
Inventors: |
KIM; In Ho; (Busan, KR)
; LEE; Jin Won; (Pohang-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
POSTECH ACADEMY-INDUSTRY FOUNDATION |
Pohang-si, Gyeongsangbuk-do |
|
KR |
|
|
Assignee: |
POSTECH ACADEMY-INDUSTRY
FOUNDATION
Pohang-si, Gyeongsangbuk-do
KR
|
Family ID: |
48866591 |
Appl. No.: |
14/652045 |
Filed: |
October 25, 2013 |
PCT Filed: |
October 25, 2013 |
PCT NO: |
PCT/KR2013/009555 |
371 Date: |
June 12, 2015 |
Current U.S.
Class: |
34/391 ; 134/7;
34/367 |
Current CPC
Class: |
F26B 3/34 20130101; F26B
19/00 20130101; F26B 3/36 20130101; F26B 5/04 20130101; B08B 3/04
20130101; F26B 5/00 20130101; B24C 1/003 20130101 |
International
Class: |
F26B 5/00 20060101
F26B005/00; F26B 19/00 20060101 F26B019/00; B08B 3/04 20060101
B08B003/04 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 18, 2012 |
KR |
10-2012-0148974 |
Claims
1. A method of removing a liquid membrane using a high-speed
particle beam, the method comprising: a wet washing step of washing
an object using a washing solution; and a dry washing step of
simultaneously removing the washing solution remaining on the
object and pollutants or foreign substances contained in the
washing solution by injecting sublimation particles, wherein the
dry washing step is characterized in that a particle generation gas
passing through a nozzle including a first dilating portion and a
second dilating portion is injected onto the object and an average
dilation angle of the second dilating portion is wider than a
dilation angle of the first dilating portion, and the dry washing
step includes: a nucleus generation step of generating nuclei as
the particle generation gas rapidly expands while passing through
an orifice provided in a nozzle throat of the nozzle; a particle
generation step of generating the sublimation particles as growth
of nuclei is accomplished while the particle generation gas passes
through the first dilating portion extended from an outlet of the
nozzle throat, after performing the nucleus generation step; and a
particle acceleration step of offsetting growth of a boundary layer
and increasing speed of injecting the sublimation particles as the
particle generation gas passes through the second dilating portion
extended from an outlet of the first dilating portion and having
the average dilation angle wider than the dilation angle of the
first dilating portion, after performing the particle generation
step.
2. The method according to claim 1, further comprising a drying
step of drying the object, performed together with the dry washing
step so that condensation of moisture may not occur on a surface of
the object as the surface of the object is cooled down by the
sublimation particles in the dry washing step.
3. The method according to claim 2, wherein the drying step
includes a heating step of heating the object by providing a
heating device under the object.
4. The method according to claim 2, wherein the drying step
includes a nitrogen injection step of drying the surface of the
object by injecting nitrogen on the object.
5. The method according to claim 1, wherein the dry washing step is
performed inside a tightly sealed chamber, and the chamber is
filled with carbon dioxide or nitrogen so that condensation of
moisture may not occur on a surface of the object as the surface of
the object is cooled down by the sublimation particles.
6. The method according to claim 1, further comprising: a first
transfer step of loading the object onto a dry washing position
after performing the wet washing step; and a second transfer step
of unloading the object from the dry washing position after
performing the dry washing step.
7. The method according to claim 1, wherein the particle generation
gas is formed of carbon dioxide, and the first dilating portion has
a dilation angle of 0.degree. and 30.degree., whereas the second
dilating portion has an average dilation angle increased by
10.degree. to 45.degree. compared with the dilation angle of the
first dilating portion.
8. The method according to claim 7, wherein the dry washing step
further includes, after performing the particle acceleration step,
a flow control step of forming a high-speed core of the sublimation
particles outside the nozzle as the particle generation gas passes
through the third dilating portion extended from an outlet of the
second dilating portion and having a dilation angle increased by
10.degree. to 45.degree. compared with the average dilation angle
of the second dilating portion and lower than 90.degree. in
maximum.
9. A method of removing a liquid membrane using a high-speed
particle beam, the method comprising: a dry washing step of
removing the liquid membrane existing on an object and foreign
substances or pollutants contained in the liquid membrane by
injecting sublimation particles, wherein the dry washing step is
characterized in that a particle generation gas passing through a
nozzle including a first dilating portion and a second dilating
portion is injected onto the object and an average dilation angle
of the second dilating portion is wider than a dilation angle of
the first dilating portion, and the dry washing step includes: a
nucleus generation step of generating nuclei as the particle
generation gas rapidly expands while passing through an orifice
provided in a nozzle throat of the nozzle; a particle generation
step of generating the sublimation particles as growth of nuclei is
accomplished while the particle generation gas passes through the
first dilating portion extended from an outlet of the nozzle
throat, after performing the nucleus generation step; and a
particle acceleration step of offsetting growth of a boundary layer
and increasing speed of injecting the sublimation particles as the
particle generation gas passes through the second dilating portion
extended from an outlet of the first dilating portion and having
the average dilation angle wider than the dilation angle of the
first dilating portion, after performing the particle generation
step.
10. The method according to claim 9, further comprising a drying
step of drying the object, performed together with the dry washing
step so that condensation of moisture may not occur on a surface of
the object as the surface of the object is cooled down by the
sublimation particles in the dry washing step.
11. The method according to claim 10, wherein the drying step
includes a heating step of heating the object by providing a
heating device under the object.
12. The method according to claim 10, wherein the drying step
includes a nitrogen injection step of drying the surface of the
object by injecting nitrogen on the object.
13. The method according to claim 9, wherein the dry washing step
is performed inside a tightly sealed chamber, and the chamber is
filled with carbon dioxide or nitrogen so that condensation of
moisture may not occur on a surface of the object as the surface of
the object is cooled down by the sublimation particles.
14. The method according to claim 9, further comprising: a first
transfer step of loading the object onto a dry washing position as
a prior step of the dry washing step.
15. The method according to claim 9, wherein in the dry washing
step, the particle generation gas is formed of carbon dioxide, and
the first dilating portion has a dilation angle of 0.degree. and
30.degree., whereas the second dilating portion has an average
dilation angle increased by 10.degree. to 45.degree. compared with
the dilation angle of the first dilating portion.
16. The method according to claim 15, wherein the dry washing step
further includes, after performing the particle acceleration step,
a flow control step of forming a high-speed core of the sublimation
particles outside the nozzle as the particle generation gas passes
through the third dilating portion extended from an outlet of the
second dilating portion and having a dilation angle increased by
10.degree. to 45.degree. compared with the average dilation angle
of the second dilating portion and lower than 90.degree. in
maximum.
17. The method according to claim 3, wherein the drying step
includes a nitrogen injection step of drying the surface of the
object by injecting nitrogen on the object.
18. The method according to claim 11, wherein the drying step
includes a nitrogen injection step of drying the surface of the
object by injecting nitrogen on the object.
Description
TECHNICAL FIELD
[0001] The present invention relates to a method of removing a
liquid membrane using a high-speed particle beam, and more
specifically, to a method of removing various pollutants contained
in a liquid, as well as the liquid forming a liquid membrane, by
radiating a high-speed particle beam onto the liquid membrane
remaining on the surface of a washing object after performing wet
washing.
BACKGROUND ART
[0002] In a general wet washing process, a process of washing the
surface of a washing object using a washing solution is performed
to remove foreign substances or pollutants attached on the surface
of the washing object. In this process, it is general that the
washing solution is injected at a high speed or churned using
ultrasonic waves or the like to enhance efficiency of washing.
[0003] Meanwhile, after the washing process is finished, some of
the washing solution and the foreign substances or pollutants
always remain on the surface of the washing object.
[0004] It is apparent that some of the foreign substances or
pollutants remain in the washing solution after the washing is
finished as described above, and, in addition, molecules or ions of
an additive added to the washing solution to improve cleaning power
remain together with the washing solution. Therefore, it is general
to Perform an additional drying process to remove the washing
solution remaining as described above.
[0005] Although liquid materials (solvents) forming the washing
solution is quickly removed in the drying process through
evaporation, a large amount of melt or floating materials is not
removed and still remains on the surface, and thus a separate
removing process is additionally required.
[0006] In addition, there is a problem in that a secondary defect
occurs due to the remaining materials.
DISCLOSURE OF INVENTION
Technical Problem
[0007] Therefore, the present invention has been made in view of
the above problems, and it is an object of the present invention to
provide a method of removing a liquid membrane using a high-speed
particle beam, which can simultaneously remove a washing solution
remaining on an object and pollutants or foreign substances
contained in the washing solution after performing a wet washing
process.
Technical Solution
[0008] To accomplish the above object, according to one aspect of
the present invention, there is provided a method of removing a
liquid membrane using a high-speed particle beam, the method
including: a wet washing step of washing an object using a washing
solution, and a dry washing step of simultaneously removing the
washing solution remaining on the object and pollutants or foreign
substances contained in the washing solution by injecting
sublimation particles.
Advantageous Effects
[0009] Since the method of removing a liquid membrane using a
high-speed particle beam according to the present invention may
simultaneously remove the liquid membrane formed on an object and
pollutants or foreign substances contained therein in one process,
the problem of remaining the pollutants or foreign substances on
the object can be solved in comparison with a conventional method
of simply drying the liquid membrane, and thus it is effective in
that an additional process is not required to solve the problem,
and a secondary defect caused by the remaining materials can be
prevented in advance.
[0010] In addition, since an additional wet washing process for
removing the remaining materials is not required, it has an effect
of preventing environmental pollution by reducing chemical
wastewater.
[0011] In addition, since additional washing processes can be
reduced remarkably, productivity, economic efficiency and spatial
efficiency can be improved simultaneously.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a view schematically showing the main concept of a
method of removing a liquid membrane using a high-speed particle
beam according to an embodiment of the present invention.
[0013] FIGS. 2 and 3 are flowcharts illustrating a method of
removing a liquid membrane using a high-speed particle beam
according to an embodiment of the present invention, which includes
a wet washing step.
[0014] FIG. 4 is a cross-sectional view showing a nozzle used in a
dry washing step according to an embodiment of the present
invention.
[0015] FIG. 5 is a view showing major parts configuring a dry
washing device used in a dry washing step according to an
embodiment of the present invention.
DESCRIPTION OF SYMBOLS
[0016] 1: Object
[0017] 2: Liquid membrane, Washing solution
[0018] 3: Pollutant or Foreign substance
[0019] 10: Nozzle
[0020] 11: Nozzle throat
[0021] 12: Orifice
[0022] 13: Orifice block
[0023] 14: First dilating portion
[0024] 15: Second dilating portion
[0025] 16: Third dilating portion
[0026] 17: Gas supply tube
[0027] 18: Heat insulation unit
[0028] 19: Nozzle axis
[0029] 20: Pressure controller
[0030] 30: Mixing chamber
[0031] 40: Particle generation gas storage unit
[0032] 50: Carrier gas storage unit
[0033] .theta..sub.1, .theta..sub.2, .theta..sub.3: Dilation
angle
BEST MODE FOR CARRYING OUT THE INVENTION
[0034] Hereafter, specific contents for embodying the present
invention will be described in detail with reference to the
accompanying drawings.
[0035] FIG. 1 is a view schematically showing the main concept of a
method of removing a liquid membrane using a high-speed particle
beam according to an embodiment of the present invention. FIG. 1(a)
shows a liquid membrane formed on an object and pollutants or
foreign substances contained therein, and FIG. 1(b) shows an object
of a washed state.
[0036] As shown in FIG. 1, a method of removing a liquid membrane
using a high-speed particle beam according to the present invention
corresponds to a method of removing a liquid membrane 2 formed on
the surface of an object 1 and pollutants or foreign substances 3
contained in the liquid membrane 2 by injecting sublimation
particles.
[0037] First, the method of removing a liquid membrane using a
high-speed particle beam according to an embodiment of the present
invention relates to removing washing solution remaining on the
object 1 and the pollutants or foreign substances 3 contained in
the washing solution after performing a wet washing step. The
liquid membrane 2 shown in FIG. 1 can be regarded as washing
solution remaining after the wet washing step is performed.
Hereinafter, a reference numeral `2`, which is the same as that of
the liquid membrane, will be used for the washing solution.
[0038] FIGS. 2 and 3 are flowcharts illustrating a method of
removing a liquid membrane using a high-speed particle beam, which
includes the wet washing step.
[0039] As shown in FIGS. 2 and 3, the method of removing a liquid
membrane using a high-speed particle beam according to an
embodiment of the present invention is configured to include a wet
washing step, a first transfer step, a dry washing step and a
second transfer step.
[0040] First, the wet washing step is a process of washing an
object 1 using a washing solution 2. The washing solution 2 is
inevitably remained on the surface of the object 1 passing through
the wet washing step, and pollutants or foreign substances 3 are
contained in the remaining washing solution 2. For example, various
organic materials, metallic impurities, alkaline ions, hydroxide
materials may be the pollutants or foreign substances 3.
[0041] The dry washing step is a process of simultaneously removing
the washing solution 2 and the pollutants or foreign substances 3
contained therein by injecting sublimation particles. Although it
is general in the prior art that the washing solution 2 is
evaporated by simply adding a drying process after wet washing, in
this case, there is a problem in that materials having a property
not being evaporated, among the pollutants or foreign substances 3
contained in the washing solution 2, still remain on the surface of
the object 1. In addition, the washing solution 2 has a problem of
remaining stains because of various additives. The dry washing step
removes the washing solution 2 together with the pollutants or
foreign substances 3 by injecting sublimation particles to solve
such a problem.
[0042] On the other hand, it is preferable that the dry washing
step is progressed together with a drying step as shown in FIG. 2.
Although the drying step of the prior art is a process for simply
evaporating the washing solution 2, the drying step of the present
invention is a process of preventing condensation of moisture on
the surface of the object 1 which occurs due to a cooling effect
caused by the sublimation particles and immediately evaporating
moisture although there is some condensed moisture. It may be
considered to include a heating step of heating the object 1 in
such a drying step by providing a heating device such as a hot
plate or the like under the object 1. On the other hand, the drying
step may include a nitrogen injection step of drying the surface of
the object by injecting nitrogen on the object 1. Although the
heating step and the nitrogen injection step may be separately
performed, it is further preferable to simultaneously perform the
steps.
[0043] In addition, as shown in FIG. 3, the dry washing step is
preferably configured of detailed steps including a nucleus
generation step, a particle generation step, a particle
acceleration step and a flow control step.
[0044] The dry washing step includes a series of processes for
generating sublimation particles by passing a particle generation
gas through a nozzle 10 and accelerating and injecting the
sublimation particles on the object 1.
[0045] FIG. 4 is a cross-sectional view showing a nozzle used in
the dry washing step, and FIG. 5 is a view showing major parts
configuring a dry washing device including a nozzle. Hereinafter,
each of the detailed steps will be described in detail with
reference to the figures.
[0046] First, the nucleus generation step of generating nuclei is
performed as a particle generation gas rapidly expands while
passing through an orifice 12 provided in a nozzle throat 11 of the
nozzle 10. Generation of nuclei can be induced at a room
temperature without a separate cooling device by providing an
orifice 12 having a microscopic hole to rapidly expand the particle
generation gas, and it may be also possible to generate nuclei of a
uniform size as the particle generation gas rapidly expands.
[0047] Then, after performing the nucleus generation step, the
particle generation step of generating sublimation particles is
performed as growth of nuclei is accomplished while the particle
generation gas passes through a first dilating portion 14 extended
from the outlet of the nozzle throat 11 and having a dilation angle
.theta..sub.1 of 0.degree. to 30.degree.. The first dilating
portion 14 is formed to have a comparatively gentle dilation angle
.theta..sub.1 compared with a second dilating portion 15 and
provides a sufficient time for the nuclei to grow.
[0048] Then, after performing the particle generation step, the
particle acceleration step of offsetting growth of a boundary layer
and increasing the speed of injecting the sublimation particles is
performed as the particle generation gas passes through the second
dilating portion 15 extended from the outlet of the first dilating
portion 14 and having an average dilation angle .theta..sub.2
increased by 10.degree. to 45.degree. compared with the dilation
angle .theta..sub.1 of the first dilating portion 14. Although the
first dilating portion 14 is formed to be comparatively long at a
comparatively gentle dilation angle .theta..sub.1 and induces
growth of nuclei, it invites reduction of flowing speed since an
effective area is reduced as the boundary layer is increased.
Accordingly, the second dilating portion 15 capable of obtaining an
additional accelerating force is provided to compensate the
reduction of speed.
[0049] Meanwhile, since the second dilating portion 15 does not
have a single dilation angle unlike the first dilating portion 14
and a third dilating portion, the angle is referred to as an
average angle. If the dilation angle at the connection portion of
the second dilating portion 15 is changed significantly in steps
when the second dilating portion 15 is extended from the first
dilating portion 14, an internal shock wave will be generated.
Accordingly, the second dilating portion 15 is preferably formed in
a shape having curves. Further specifically, the connection portion
for connecting the second dilating portion 15 to the first dilating
portion 14 is formed to have a dilation angle the same as the
dilation angle .theta..sub.1 of the outlet side of the first
dilating portion 14, and the connection portion is formed to
gradually increase the dilation angle toward the center of the
second dilating portion 15 to form an acute inclination angle near
the center and decrease the dilation angle from the center toward
the outlet side of the second dilating portion 15 so that
generation of the internal shock wave may be prevented.
[0050] It is preferable to further include, after performing the
particle acceleration step, the flow control step of forming a
high-speed core of the sublimation particles outside the nozzle 10
as the particle generation gas passes through the third dilating
portion 16 extended from the outlet of the second dilating portion
15 and having a dilation angle .theta..sub.3 increased by
10.degree. to 45.degree. compared with the average dilation angle
.theta..sub.2 of the second dilating portion 15 and lower than
90.degree. in maximum. If back pressure at the rear end of the
nozzle 10 is low, a flow field may additionally grow since a
separation point goes farther from the nozzle throat 11, and thus
it is preferable to form the third dilating portion 16 to induce
the separation point to be positioned at the end portion of the
dilating portion while securing a sufficient length at the same
time. It is since that washing efficiency can be increased greatly
by forming the high-speed core (isentropic core) outside the nozzle
10.
[0051] On the other hand, if the back pressure at the rear end of
the nozzle 10 is formed to be high, it may be regarded that the
flow field has already grown sufficiently since the separation
point comes closer to the nozzle throat 11, and thus it is
preferable to expose the high-speed core at the outside of the
nozzle 10 by reducing the length of the third dilating portion
16.
[0052] On the other hand, the dry washing step may be divided into
i) a case of using a mixture of a particle generation gas and a
carrier gas and ii) a case of using only a particle generation
gas.
[0053] Here, carbon dioxide or argon may be considered as the
particle generation gas, and helium or nitrogen may be considered
as the carrier gas.
[0054] In the case of using a mixture of a particle generation gas
and a carrier gas, a particle generation gas storage unit 40 and a
carrier gas storage unit 50 are connected to a mixing chamber 30.
The mixing chamber 30 performs a function of sufficiently mixing
the particle generation gas and the carrier gas and, at the same
time, adjusting a mixing ratio. It is preferable that the mixing
ratio is adjusted to form a carbon dioxide mixture gas by mixing
the carrier gas with the particle generation gas so that mixing the
carrier gas may occupy 10 to 99% of the total volume of the
mixture.
[0055] The mixture gas mixed in the mixing chamber 30 flows into a
pressure controller 20. The pressure controller 20 controls
pressure for supplying the mixture gas to the nozzle 10.
[0056] On the other hand, in the case of using only a particle
generation gas, it may be considered to supply the particle
generation gas to the pressure controller 20 by directly connecting
the particle generation gas storage unit 40 to the pressure
controller 20 without passing through the mixing chamber 30.
Hereinafter, a particle generation gas of the case using only a
particle generation gas will be referred to as a pure particle
generation gas as a concept contrasting to the mixture gas.
[0057] In addition, it is preferable that output pressure at the
pressure controller 20 is formed within a range of i) 5 to 120 bar
in the case of the mixture gas and ii) 5 to 60 bar in the case of
the pure particle generation gas, considering the size and
injection speed of the generated sublimation particles.
[0058] The mixture gas or the pure particle generation gas passing
through the pressure controller 20 is supplied to the inlet of the
nozzle 10.
[0059] The mixture gas or the pure particle generation gas supplied
to the inlet of the nozzle 10 sequentially passes through the
orifice 12, the first dilating portion 14 and the second dilating
portion 15 as described above, and sublimation nano-particles are
injected onto the object 1.
[0060] On the other hand, in the case of supplying only the pure
particle generation gas, a pressure control step of adjusting the
pressure of the particle generation gas is performed without
performing the mixing step.
[0061] Here, it is preferable that pressure of the particle
generation gas passing through the pressure control step is
controlled to 5 to 60 bar to flow the particle generation gas into
the nozzle 10.
[0062] The steps following thereafter are the same as the nucleus
generation step, the particle generation step, the particle
acceleration step and the flow control step.
[0063] On the other hand, it may be considered to perform the dry
washing step inside a tightly sealed chamber, and the chamber is
preferably filled with carbon dioxide or nitrogen so that
condensation of moisture may not occur on the surface of the object
1 as the surface of the object 1 is cooled down by the sublimation
particles. On the other hand, it may be considered to prevent
condensation of moisture by separately injecting carbon dioxide or
nitrogen directly onto the object 1 although the dry washing step
is not performed inside the tightly sealed chamber.
[0064] In addition, it is preferable to further include a first
transfer step of loading the object 1 onto a dry washing position
as a prior step of the dry washing step, and it will be preferable
to further include a second transfer step of unloading the object 1
from the dry washing position after performing the dry washing step
so that the dry washing work may be performed as a comprehensive
process.
[0065] An embodiment of removing a liquid membrane generated in a
wet washing step is described above. The method of removing a
liquid membrane using a high-speed particle beam according to the
present invention may be applied to various processes in which
liquid, including the washing solution 2, remains on the surface of
an object 1 after the wet washing step is performed.
[0066] For example, the method of the present invention may be
applied to a variety of fields requiring removal of a liquid
membrane 2 formed on an object 1 and pollutants or foreign
substances 3 contained therein, such as washing lubricant remaining
on a sample after processing the sample in a milling process using
the lubricant, washing various display panels, washing a solar
power generation panel, washing an optical lens and the like. In
this case, the wet washing step may be replaced with all the
processes in which a liquid membrane 2 is formed on an object
1.
[0067] The positional relations used to describe a preferred
embodiment of the present invention are described focusing on the
accompanying drawings, and the positional relations may be changed
according to the aspect of an embodiment.
[0068] In addition, unless otherwise defined, all terms used in the
present invention, including technical or scientific terms, have
the same meanings as those generally understood by those with
ordinary knowledge in the field of art to which the present
invention belongs. In addition, the terms should not be interpreted
to have ideal or excessively formal meanings unless clearly defined
in the present application.
[0069] Although the preferred embodiment of the present invention
has been described above, it should be regarded that embodiments
simply aggregating prior arts with the present invention or simply
modifying the present invention, as well as the present invention,
also fall within the scope of the present invention.
* * * * *